Battery pack for failure safety

ABSTRACT

An electric aircraft with a battery pack for failure safety is provided. The battery pack may be disposed within a fuselage of the electric aircraft. The battery pack may include a crush zone having energy absorbing material configured to compress as a function of a crash force.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of Nonprovisional application Ser.No. 17/319,201, filed on May 13, 2021, and entitled “BATTERY PACK FORFAILURE SAFETY,” the entirety of which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention generally relates to the field of batteries. Inparticular, the present invention is directed to a battery pack forfailure safety.

BACKGROUND

Battery packs are built to be stiff external shells to protect thebatteries inside from impact forces. However large impact forces willoften result in thermal runaway as a function of the limited amount ofrigid protection. This leads to hazardous conditions and uncontrolledcombustion, which puts many individuals in harmful situations.

SUMMARY OF THE DISCLOSURE

In an aspect, an electric aircraft with a battery pack for failuresafety is provided. The electric aircraft includes a fuselage having alongitudinal axis. The electric aircraft includes a battery packdisposed within the fuselage. The battery pack includes a pack casingmounted to the fuselage, wherein the pack casing comprises an innerlining. The battery pack also includes a crush zone positionedperpendicular to the longitudinal axis, wherein the crush zone includesan energy absorbing material configured to compress as a function of acrash force.

These and other aspects and features of non-limiting embodiments of thepresent invention will become apparent to those skilled in the art uponreview of the following description of specific non-limiting embodimentsof the invention in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, the drawings show aspectsof one or more embodiments of the invention. However, it should beunderstood that the present invention is not limited to the precisearrangements and instrumentalities shown in the drawings, wherein:

FIG. 1 is a diagrammatic representation of an exemplary embodiment of abattery pack for failure safety;

FIG. 2 are diagrammatic representations illustrating various states ofan exemplary embodiment of a battery pack for failure safety;

FIG. 3 is a block diagram of an energy absorbing material according toan embodiment of the invention; and

FIG. 4 is a diagrammatic representation of an exemplary embodiment of anaircraft.

The drawings are not necessarily to scale and may be illustrated byphantom lines, diagrammatic representations and fragmentary views. Incertain instances, details that are not necessary for an understandingof the embodiments or that render other details difficult to perceivemay have been omitted.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present invention. It will be apparent, however,that the present invention may be practiced without these specificdetails. As used herein, the word “exemplary” or “illustrative” means“serving as an example, instance, or illustration.” Any implementationdescribed herein as “exemplary” or “illustrative” is not necessarily tobe construed as preferred or advantageous over other implementations.All of the implementations described below are exemplary implementationsprovided to enable persons skilled in the art to make or use theembodiments of the disclosure and are not intended to limit the scope ofthe disclosure, which is defined by the claims. For purposes ofdescription herein, the terms “upper”, “lower”, “left”, “rear”, “right”,“front”, “vertical”, “horizontal”, and derivatives thereof shall relateto the invention as oriented in FIG. 1 . Furthermore, there is nointention to be bound by any expressed or implied theory presented inthe preceding technical field, background, brief summary or thefollowing detailed description. It is also to be understood that thespecific devices and processes illustrated in the attached drawings, anddescribed in the following specification, are simply exemplaryembodiments of the inventive concepts defined in the appended claims.Hence, specific dimensions and other physical characteristics relatingto the embodiments disclosed herein are not to be considered aslimiting, unless the claims expressly state otherwise.

At a high level, aspects of the present disclosure are directed to abattery pack for failure safety. In an embodiment, this allows forenhanced safety of a battery experiencing a vertical drop such as acrash landing and/or hard landing. This is so, at least in part, becausethe battery pack incorporates a crush zone located beneath a batterymodule that comprises an energy absorbing material configured tocompress as a function of a crash force. Aspects of the presentdisclosure allow for a battery pack for failure safety. Exemplaryembodiments illustrating aspects of the present disclosure are describedbelow in the context of several specific examples.

Referring now to the drawings, FIG. 1 illustrates an exemplary method ofa battery pack 100 for failure safety. Battery pack 100 includes a packcasing 104. As used in this disclosure a “pack casing” is a rigidcompartment and/or chamber that may hold and/or protect a plurality ofcomponents. In an embodiment, pack casing may include one or morematerials capable of protecting the plurality of components locatedinside of the compartment and/or chamber. For example, and withoutlimitation, a material may consist of wood, aluminum, steel, titanium,polymers, graphite-epoxy, composites, and the like thereof. As a furthernon-limiting example, pack casing 104 may include a material such aspolycarbonate, acrylonitrile butadiene styrene, polypropylene, highimpact polystyrene, and the like thereof. In an embodiment, pack casingmay include an upper wall. As used in this disclosure an “upper wall” isa piece of material that encloses the upper portion of the compartment,wherein a material may include any of the materials as described above;upper wall may be or include a continuous piece of material. Forexample, upper wall may include a sheet of polypropylene that protectsthe compartment and or chamber from objects and/or the environmentlocated above pack casing 104. In an embodiment, upper wall of packcasing 104 may include a recess 108 located along a central longitudinalaxis 108. As used in this disclosure a “central longitudinal axis” is adirectional axis that extends along a longitudinal direction from therear of the pack casing to the front of the pack casing. Pack casing 104may include at least a side wall. As used in this disclosure a “sidewall” is a piece of material that encloses one or more lateral portionsof the compartment; side wall may be or include a continuous piece ofmaterial. Side wall may be configured with a high compression strengthelement. As used in this disclosure a “high compression strengthelement” is an element that has a large hardness rating and/or resistsbeing squeezed together. In an embodiment high compression strengthelement may be determined as a function of a Mohs scale. For example andwithout limitation, a high compression strength element may include amaterial that has a 9 mohs scale value. In yet another embodiment, highcompression strength element may be determined as a function of aVickers hardness test. For example and without limitation, a highcompression strength element may include a material that has a 180HV30HV value. Pack casing 104 may include a lower wall. In yet anotherembodiment, high compression strength element may include one or morearrangements of materials such as a honeycomb arrangement. In yetanother embodiment, high compression strength element may include one ormore element such as a foam and/or polymer described below. As used inthis disclosure a “lower wall” is a piece of material that encloses thelower and/or bottom portion of the compartment; lower wall may be orinclude a continuous piece of material wherein a material may includeany of the materials as described above. Lower wall may include one ormore walls and/or materials that contact a ground below pack casing 104.

Still referring to FIG. 1 , pack casing 104 is configured with an innerlining 112. As used in this disclosure an “inner lining” is an innerpanel located within pack casing 104 that guides and/or directs batterymodule 116 towards energy compressing material 124 as a function of oneor more grooved fittings. For example, and without limitation, innerlining may include one or more guide rail systems that adopt a groovedstructure and are arranged to orient and/or guide a falling and/ormoving object in a direction. In an embodiment, inner lining 112 may besecured to the side wall of pack casing 104 to guide battery module 116.Inner lining 112 may be secured as a function of one or more attachingmechanisms such as bolting, riveting, welding, press fitting, and thelike thereof as described above in detail. Further, inner lining 112 maybe secured as a function of one or more blind and/or pop rivets, solidand/or round head rivets, oxy-acetylene welds, electric arc welds,shielded metal arc welds, gas metal arc welds, composite press-fitinserts, and/or one or more locking methods such as, but not limited tofriction locking methods, mechanical locking methods, adhesive lockingmethods, and the like thereof. In yet another embodiment, inner lining112 may be composed of one or more rigid elements that at least providestructure for battery module 116 to be guided. For example, and withoutlimitation, inner lining 112 may be composed of one or more rigidelements such as polycarbonate, acrylonitrile butadiene styrene,polypropylene, high impact polystyrene, perfluoroalkoxy alkane,polytetrafluoroethylene, polyvinylidene fluoride, ceramic, and the likethereof. As a further non-limiting example, inner lining 112 may includeone or more metals such as stainless steel, duplex alloys, nickel,nickel-based alloys, titanium, titanium alloys, and the like thereof.

Still referring to FIG. 1 , battery pack 100 includes a battery module116 of a plurality of battery modules. As used in this disclosure a“battery module” is a module comprising a plurality of battery cellswired together in series and/or in parallel. In an embodiment, andwithout limitation, battery cells may be wired together using anyconnection permitting electric conduction, such as but not limited toplug and socket connectors, crimp-on connectors, soldered connectors,insulation-displacement connectors, binding posts, screw terminals, ringand spade connectors, blade connectors, and the like thereof. In anembodiment, battery module 116 may be disposed between upper wall, sidewall, and/or lower wall such that they are enclosed within at least 4sides of the pack casing 104. In an embodiment, a battery module may bedisposed in or on an eVTOL aircraft and may provide power to at least aportion of an aircraft in flight or on the ground, for example, thebattery module may provide power within an entire flight envelope of anaircraft including, for example, emergency procedures. In an embodiment,and without limitation, battery module 116 may be used to provide asteady supply of electrical power to a load over the course of a flightby a vehicle or other electric aircraft. For example, the battery module116 may be capable of providing sufficient power for “cruising” andother relatively low-energy phases of flight. Battery module 116 mayalso be capable of providing electrical power for some higher-powerphases of flight as well, particularly when the energy source is at ahigh SOC, as may be the case for instance during takeoff. In anembodiment, battery module 116 may be capable of providing sufficientelectrical power for auxiliary loads including without limitation,lighting, navigation, communications, de-icing, steering or othersystems requiring power or energy. Further, battery module 116 may becapable of providing sufficient power for controlled descent and landingprotocols, including, without limitation, hovering descent or runwaylanding. As used herein batter module 116 may have high power densitywhere the electrical power the battery module may usefully produce perunit of volume and/or mass is relatively high. The electrical power isdefined as the rate of electrical energy per unit time. Battery module116 may include a device for which power that may be produced per unitof volume and/or mass has been optimized, at the expense of the maximaltotal specific energy density or power capacity, during design.

The battery module, as a whole, may comprise hardware for mechanical andelectrical coupling to at least a portion of eVTOL aircraft. In anembodiment battery module 116 may include a plurality of battery cells.Battery cells may be disposed and/or arranged within a respectivebattery module 116 in groupings of any number of columns and rows. Forexample and without limitation, battery cells may be arranged in batterymodule 116 with 18 cells in two columns. One of skill in the art willunderstand that battery cells may be arranged in any number to a row andin any number of columns and further, any number of battery cells may bepresent in battery module 116. In an embodiment and without limitation,battery cells within a first column may be disposed and/or arranged suchthat they are staggered relative to battery cells within a secondcolumn. In this way, any two adjacent rows of battery cells may not belaterally adjacent but instead may be respectively offset apredetermined distance. In another embodiment, any two adjacent rows ofbattery cells may be offset by a distance equal to a radius of a batterycell. This arrangement of battery cells is only a non-limiting exampleand in no way preclude other arrangement of battery cells.

Still referring to FIG. 1 , battery cells may each comprise a cellconfigured to include an electrochemical reaction that produceselectrical energy sufficient to power at least a portion of an eVTOLaircraft. Battery cell may include electrochemical cells, galvaniccells, electrolytic cells, fuel cells, flow cells, voltaic cells, or anycombination thereof—to name a few. In an embodiment, battery cells maybe electrically connected in series, in parallel, or a combination ofseries and parallel. As used in this disclosure a “series connection” iswiring a first terminal of a first cell to a second terminal of a secondcell and further configured to comprise a single conductive path forelectricity to flow while maintaining the same current (measured inAmperes) through any component in the circuit. Battery cells may use theterm ‘wired,’ but one of ordinary skill in the art would appreciate thatthis term is synonymous with ‘electrically connected’, and that thereare many ways to couple electrical elements like battery cells together.For example and without limitation, battery cells can be coupled viaprefabricated terminals of a first gender that mate with a secondterminal with a second gender. As used in this disclosure a “parallelconnection” is wiring a first and second terminal of a first batterycell to a first and second terminal of a second battery cell and furtherconfigured to comprise more than one conductive path for electricity toflow while maintaining the same voltage (measured in Volts) across anycomponent in the circuit. Battery cells may be wired in aseries-parallel circuit which combines characteristics of theconstituent circuit types to this combination circuit. Battery cells maybe electrically connected in any arrangement which may confer onto thesystem the electrical advantages associated with that arrangement suchas high-voltage applications, high-current applications, or the like. Asused in this disclosure an “electrochemical cell,” is a device capableof generating electrical energy from chemical reactions or usingelectrical energy to cause chemical reactions. Further, voltaic orgalvanic cells are electrochemical cells that generate electric currentfrom chemical reactions, while electrolytic cells generate chemicalreactions via electrolysis. Non-limiting examples of battery cells mayinclude batterie cells used for starting applications including Li ionbatteries cells which may include NCA, NMC, Lithium iron phosphate(LiFePO4) and Lithium Manganese Oxide (LMO) batteries, which may bemixed with another cathode chemistry to provide more specific power ifthe application requires Li metal batteries, which have a lithium metalanode that provides high power on demand, Li ion batteries that have asilicon or titanite anode, energy source may be used, in an embodiment,to provide electrical power to an electric aircraft or drone, such as anelectric aircraft vehicle, during moments requiring high rates of poweroutput, including without limitation takeoff, landing, thermal de-icingand situations requiring greater power output for reasons of stability,such as high turbulence situations. A battery cell may include, withoutlimitation a battery cell using nickel based chemistries such as nickelcadmium or nickel metal hydride, a battery cell using lithium ionbattery chemistries such as a nickel cobalt aluminum (NCA), nickelmanganese cobalt (NMC), lithium iron phosphate (LiFePO4), lithium cobaltoxide (LCO), and/or lithium manganese oxide (LMO), a battery cell usinglithium polymer technology, lead-based batteries such as withoutlimitation lead acid batteries, metal-air batteries, or any othersuitable battery. Persons skilled in the art, upon reviewing theentirety of this disclosure, will be aware of various devices ofcomponents that may be used as battery cells.

Still referring to FIG. 1 , battery module 116 is secured to pack casing104 by a battery module connection. As used in this disclosure a“battery module connection” is a component and/or mechanism that securesbattery module 116 to pack casing 104. Battery module connection may beaccomplished, without limitation, by bolting, riveting, welding, pressfitting, and the like thereof. For example, and without limitation asolid and/or round head rivet may be used to attach battery module 116to pack casing 104. As a further non-limiting example, a blind and/orpop rivet may be used to attach battery module 116 to pack casing 104.As a further non-limiting example, an oxy-acetylene weld and/or electricarc weld may be used to attach battery module 116 to pack casing 104. Asa further non-limiting example, a shielded metal arc weld and/or gasmetal arc weld may be used to attach battery module 116 to pack casing104. As a further non-limiting example, a composite press-fit insert maybe used to attach battery module 116 to pack casing 104. Battery moduleconnection may be accomplished, without limitation, by one or morelocking methods. For example, and without limitation battery moduleconnection may include a friction locking method that may secure batterymodule 116 to packing case 104 as a function of increasing resistancebetween contact surfaces. In an embodiment and without limitation,friction locking method may include the implementation of one or moresplit ring washers, serrated washers, tooth lock washers, nylon insertnuts, double nuts, and the like thereof. As a further non-limitingexample, battery module connection may include a mechanical lockingmethod that may secure battery module 116 to packing case 104 as afunction of a physical barrier that may prevent the fastener fromrotating. In an embodiment and without limitation, mechanical lockingmethod may include the implementation of one or more tab washers,locking wires, and the like thereof. As a further non-limiting example,battery module connection may include an adhesive locking method thatmay secure battery module 116 to packing case 104 as a function ofapplying a chemical to prevent a bolted joint from loosening. In anembodiment and without limitation, adhesive locking method may includethe implementation of one or more adhesives such as methacrylate-basedthread-locking fluids with low strength, medium strength, high strength,high temperature, penetrating, and the like thereof.

In an embodiment, and still referring to FIG. 1 , battery moduleconnection may include any means for attachment that is configured todisconnect under a predetermined load. In some cases, battery moduleconnections may be passive and rely upon loading forces fordisconnection, such as exemplary battery module connections which mayinclude one or more of a shear pin, a frangible nut, a frangible bolt, abreakaway nut, bolt, or stud, and the like. In some cases, a passivebattery module connection may include a relatively soft or brittlematerial (e.g., plastic) which is easily broken under achievable loads.Alternatively or additionally, battery module connection may include anotch, a score line, or another weakening feature purposefullyintroduced to the mount to introduce breaking at a prescribed load.According to some embodiments, a canted coil spring may be used to aspart of a battery module connection, to ensure that the mountdisconnects under a predetermined loading condition. In some cases amount may comprise a canted coil spring, a housing, and a piston; andsizes and profiles of the housing and the piston may be selected inorder to prescribe a force required to disconnect the mount.Alternatively or additionally, battery module connection may include anactive feature which is configured to actively disconnect a mount undera prescribed condition (for instance a rapid change in elevation orlarge measured G-forces). For example, and without limitation, an activemount may be configured to actively disconnect during a sensed crash. Anactive mount may, in some cases, include one or more of an explosivebolt, an explosive nut, an electro-magnetic connection, and the like. Insome cases, one or more battery module connections may be configured todisconnect under a certain loading condition, for instance a force inexcess of a predetermined threshold (i.e., battery breakaway force)acting substantially along (e.g., within about +/−45°) a predetermineddirection.

In an embodiment and still referring to FIG. 1 , pack casing 104 mayinclude an external shell to protect battery module 116. As used in thisdisclosure an “external shell” is a rigid structure that absorbs and/orprevents an initial impact energy from an external source, wherein anexternal source is one or more objects and/or items that are locatedoutside of pack casing 104. For example, and without limitation, mayinclude a rigid structure such as polycarbonate, acrylonitrile butadienestyrene, polypropylene, high impact polystyrene, perfluoroalkoxy alkane,polytetrafluoroethylene, polyvinylidene fluoride, ceramic, and the likethereof. As a further non-limiting example, external shell may includeone or more polymers such as shock absorbing polymers, visco-elasticpolymers, visco polymers, polyurethanes, and the like thereof. As afurther non-limiting example, external shell may include one or moremetals such as stainless steel, duplex alloys, nickel, nickel-basedalloys, titanium, titanium alloys, and the like thereof.

Still referring to FIG. 1 , battery pack 100 includes a crush zone 120.As used in this disclosure a “crush zone” is a region within pack casing104 that is designed to compress and/or crush to absorb a force. Crushzone 120 may be configured to prevent a thermal runaway of batterymodule 116. As used in this disclosure “thermal runaway” is anaccelerated increase in temperature of battery module 116 as a functionof current flowing through battery module 116 rapidly. For example andwithout limitation, thermal runaway may result in explosions and/oroverheating as a function of battery module 116 being physically damagedand/or harmed as a function of an external force. Crush zone 120 islocated beneath battery module 116. Crush zone may include a locationand/or region produced as a function of battery module 116 of theplurality of battery modules being secured to the upper wall of packcasing 104. Battery module may be secured to upper wall of pack casing104 as a function of one or more battery module connections. Forexample, and without limitation, crush zone 120 may include apredetermined amount of space between battery module 116 and lower wallof pack casing as a function of a plurality of nuts and bolts that maybe utilized to secure battery module 116 to the upper wall of packcasing to at least raise battery module 116. In an embodiment andwithout limitation, crush zone 120 may include a thickness parameter. Asused in this disclosure a “thickness parameter” is a predeterminedamount of distance and/or space that separates the lower wall of packingcase 104 and the bottom of battery module 116. In an embodiment andwithout limitation, thickness parameter may include a predetermineddistance of 15 cm and/or 5.91 inches. As a further non-limiting example,thickness parameter may include a predetermined distance of 2 metersand/or 78.74 inches. In an embodiment, and without limitation, thicknessparameter may be determined as a function of an impact energy. As usedin this disclosure an “impact energy” is an energy produced as afunction of an impact. For example, and without limitation, impactenergy may be determined to be 40 N, wherein the thickness parameter isadjusted to allow for an absorption of 40 N of energy.

In an embodiment and still referring to FIG. 1 , crush zone 120 may beconfigured as a to reduce an impact force. As used in this disclosure an“impact force” is a force that is generated as a function of a verticaldrop from a given height. Impact force may be generated as a function ofthe weight and/or size of the battery module falling, the velocity priorto impacting the ground, the height of the vertical drop, and/or thedistance traveled after initial impact with the ground. For example,impact force may be 40.83 N for a vertical drop of 6 meters of a 5 kgbattery module. In an embodiment and without limitation, crush zone 120may be configured to reduce impact force as a function of increasing thedistance traveled after initial impact. For example and withoutlimitation, an impact force may be 2,940,000 N for a vertical drop of3000 m of a 10 kg battery module, wherein there is no travel afterimpact, wherein an impact force may be 98,000 N for the same verticaldrop of 3000 m of a 10 kg battery module, wherein there is a 3 mdistance after initial impact. As a further non-limiting example, animpact force an aircraft vertical drop may be 2,450,000,000 N for avertical drop of 2500 m of a 10,000 kg aircraft, wherein this is notravel after impact, wherein an impact force of 49,000,000 N for thesame vertical drop of the aircraft of 2500 m of a 10,000 kg aircraft,wherein there is a 5 m distance traveled after impact. In an embodiment,and without limitation, crush zone may be determined as a function of amaximum aircraft vertical drop. As used in this disclosure a “maximumaircraft vertical drop” is the estimated vertical drop of an aircraft atits maximum height in a given flight path. For example, a maximum heightfor a flight path may be 2561 meters.

Still referring to FIG. 1 , crush zone 120 is comprised of an energyabsorbing material 124. As used in this disclosure an “energy absorbingmaterial” is a material and/or substance capable of absorbing a force.For example, and without limitation, energy absorbing material 124 mayinclude one or more energy absorbing characteristics such asconductivity, flame resistance, density, absorption, structure, and thelike thereof as described in detail below, in reference to FIG. 3 . Insome cases, energy absorbing material 124 may be configured to absorband/or dissipate energy as it is compressed. In some cases, energyabsorbing material 124 may include a material having a number of voids,for instance compressible material may take a form of a honeycomb oranother predictably cellular form. Alternatively or additionally, energyabsorbing material 124 may include a non-uniform material, such aswithout limitation a foam. As a further non-limiting example, energyabsorbing material 124 may include a polyether ether ketone material. Asa further non-limiting example, energy absorbing material 124 mayinclude a polymer foam. As a further non-limiting example, energyabsorbing material 124 may include a non-Newtonian polymer. Energyabsorbing material 124 may include a polymer and/or other dampeningmaterial such as a foam, gel, fluid, mesh, and the like thereof. Forexample, and without limitation, energy absorbing material may include apolycarbonate polymer, polypropylene polymer, polystyrene polymer,urethane foam polymer, shock absorbing polymer, visco-elastic polymer,visco polymer, and the like thereof. As a further non-limiting example,energy absorbing material may include one or more materials that reduceone or more shock energies, vibration energies, frequencies, and thelike thereof.

Still referring to FIG. 1 , energy absorbing material 124 is configuredto compress as a function of a crash force. As used in this disclosure a“crash force” is a force exerted on battery pack 100 as a function ofone or more crashes and/or impacts. In an embodiment crash force may beexerted on battery pack 100 as a function of an aircraft crash and/orvehicular crash. Energy absorbing material 124 may be configured tocompress as a function of absorbing a predetermined amount of force,wherein a predetermined amount of force may include an applied loadmagnitude acting on energy absorbing material. For example, and withoutlimitation, an applied load magnitude may act to reduce the lengthand/or thickness of energy absorbing material as a function of squeezingthe material between battery module 104 and the lower wall of packcasing 104 due to the load exceeding the compressive strength of energyabsorbing material. In another embodiment predetermined amount of forcemay include a suddenly applied load. For example, and withoutlimitation, suddenly applied load may exceed the impact strength ofenergy absorbing material 124, wherein energy absorbing material 124compresses as a function of the suddenly applied load. In yet anotherembodiment, energy absorbing material 124 may be configured to absorb apredetermined direction of force, wherein a predetermined direction offorce may include a directional load and/or force acting on energyabsorbing material. For example, and without limitation, a verticaldirection of force may result in a compression of energy absorbingmaterial 124 at a specified magnitude of force, wherein a horizontaldirection of force may result in a lesser and/or no compression ofenergy absorbing material 124. As a further non-limiting example, ahorizontal direction of force may result in a compression of energyabsorbing material 124 at a specified magnitude of force, wherein avertical direction of force may result in a lesser and/or no compressionof energy absorbing material 124.

In an embodiment, and still referring to FIG. 1 , crash force 124 mayinclude an excessive force. As used in this disclosure an “excessiveforce” is a landing force that exceeds a landing force threshold. Asused in this disclosure a “landing force threshold” is a maximum forcethat may be achieved during the landing of an aircraft. For example, andwithout limitation a landing force threshold may be a force that iscalculated relative to a specific amount of force greater than gravity,wherein the force exerted on the aircraft by gravity is determined by

$F = {G\frac{m_{1}m_{2}}{r^{2}}}$

wherein F is the force exerted on the aircraft by gravity, G is thegravitational constant, m₁ is the mass of the aircraft, m₂ is the massof the earth, and r is the distance between the centers of the masses.

In an embodiment and still referring to FIG. 1 , battery moduleconnection releases battery module 116 into crush zone 120 guided byinner lining 112. In yet another embodiment, inner lining 112 may beconfigured to guide battery module 116 to the ground. For example, andwithout limitation, inner lining 112 may be configured to allow batterymodule 116 to move in a vertical direction and/or along a y-axis. In anembodiment, and still referring to FIG. 1 , battery module connectionreleasing battery module 116 further comprises breaking a frangiblebuswork. As used in this disclosure a “frangible buswork” is one or moreconnections and/or buswork attached to battery module 116 that arefragile and/or brittle, wherein a buswork is one or more conductorsand/or group of conductors that serve as a common connection for two ormore electrical circuits. For example, and without limitation, frangiblebuswork may include one or more fuse bolts, special material bolts,frangible couplings, tear-through fasteners, tear-out sections, and thelike thereof. As a further non-limiting example, frangible buswork mayinclude one or more electrical connections such as plug and socketconnectors, crimp-on connectors, soldered connectors, binding posts,screw terminals, ring and spade connectors, blade connectors, and thelike thereof.

Still referring to FIG. 1 , battery module connection may be configuredto release battery module 116 as a function of the crash force exceedinga breakaway force. As used in this disclosure a “breakaway force” is anamount of force required to break and/or release at least a batterymodule connection that is securing battery module 116 to pack casing104. For example, and without limitation, breakaway force may include aforce of 200 N to break a battery module connection that secures batterymodule 116 from pack casing 104. As a further non-limiting example,breakaway force may include a force of 5,000 N to release a plurality ofbattery module connections that secure battery module 116 from packcasing 104. In an embodiment and without limitation, breakaway force maybe a function of the one or more attachment mechanisms securing batterymodule 116 to pack casing. For example, and without limitation,breakaway force for a nut and bolt may be 720 N, wherein breakaway forcefor an electric arc weld may be 2000 N. In this manner, one or morebreakaway forces may be established for battery module 116, prior tobreaking and/or releasing battery module connection.

In an embodiment, and still referring to FIG. 1 , breakaway force may beconfigured as a function of a predetermined amount of force. Forexample, and without limitation, a predetermined amount of force mayinclude a threshold force. As used in this disclosure a “thresholdforce” is an amount of force required to reach a threshold for releasingand/or breaking the secured attachment of battery module 116 to packcasing 104. For example, and without limitation threshold force may be6,000 N to break battery module connection, wherein breaking batterymodule connection breaks the secured attachment of battery module 116 topack casing 104 allowing battery module to be guided towards energyabsorbing material 124 as a function of inner lining 112. As a furthernon-limiting direction threshold force may include a force of 2,000 N torelease battery module connection, wherein releasing battery moduleconnection allows battery module 116 to be guided down inner lining 112and interact with energy absorbing material without breaking batterymodule connection. In an embodiment threshold force may include areleasing level. As used in this disclosure a “releasing level” is anamount of force required to release the battery module connection thatsecures battery module 116 to pack casing in a controlled and/or timedrelease. For instance, and without limitation, releasing level mayrelease battery module 116 over a 30 second release period to allow forenergy absorbing material to absorb a greater amount of impact force.

Still referring to FIG. 1 , breakaway force may be configured as afunction of a predetermined direction of force. For example, and withoutlimitation, a predetermined direction of force may denote that a forceexerted on battery module connection and/or pack casing in the verticaldirection may result in breakage of battery module connection at aspecified magnitude of force, wherein a horizontal direction of forcemay result in no breakage of battery module connection. As a furthernon-limiting example, predetermined direction of force may denote that aforce exerted on battery module connection and/or pack casing at anangle of greater than 30° may initiate a release of battery moduleconnection from pack casing, wherein releasing battery module connectionfrom pack casing results in the movement of battery module 116 downwardstowards energy absorbing material 124.

Still referring to FIG. 1 , battery pack 100 may further comprise asecondary crush zone. As used in this disclosure a “secondary crushzone” is a region within pack casing 104 that is generated as a functionof battery module 116 shifting downwards and compressing energyabsorbing material 124. In an embodiment, secondary crush zone may belocated between the upper wall of pack casing 104 and the top of batterymodule 116. For example, and without limitation, secondary crush zonemay increase in thickness as battery module 116 compresses energyabsorbing material 124. In an embodiment, the thickness of secondarycrush zone may be similar to the thickness of crush zone 120. Forexample, battery module 116 may compress energy absorbing material 124as a function of shifting downward guided by inner lining 112, whereinsecondary crush zone increases in thickness relative to the amount ofcompression that occurs in energy absorbing material 124. As a furthernon-limiting example, secondary zone compression may be 4 due to batterymodule 116 compressing energy absorbing material 124 4 cm. In anotherembodiment, secondary crush zone may protect battery module 116 from oneor more debris and/or aircraft parts. For example, and withoutlimitation, secondary crush zone may provide a predetermined distancebetween the upper wall of pack casing 104 and providing protectionimpact from external stimulus in the vertical direction, wherein thepredetermined distance is determined as a function of the thickness ofcrush zone 120. In another embodiment, secondary crush zone may protectbattery module 116 from one or more airframe impacts. As used in thisdisclosure an “airframe impact” is an impact on pack casing 104 as afunction of one or more aircraft frame parts. For example, and withoutlimitation an aircraft frame part of the fuselage may land on top ofand/or vertically impact the pack casing, wherein secondary crush zonemay provide protection for battery module 116.

Referring now to FIGS. 2A-C, an embodiment 200 of a battery pack forfailure safety is displayed. In FIG. 2A, battery module 116 is securedto upper wall of pack casing 104 as a function of a battery moduleconnector 204, wherein battery module connector 204 includes any of thebattery module connector as described above in reference to FIG. 1 .Battery module 116 is located within inner lining 112. Energy absorbingmaterial 124 is located beneath battery module 116 in an uncompressedstate. In FIG. 2B, a crash force 208 is exerted on pack casing 104,wherein crash force 208 includes any of the crash force as describedabove, in reference to FIG. 1 . Crash force 208 may be of a large enoughmagnitude to break and/or release battery module connector 204, whereinreleasing battery module connector 204 results in battery module 104being guided by inner lining 112 towards energy absorbing material 124.Energy absorbing material may begin to compress as a function of theapplied load of battery module 104 on energy absorbing material 124. InFIG. 2C, battery module 116 completes the compression of energyabsorbing material 124. For example, and without limitation, completecompression of energy absorbing material 124 may include compression of50% of the crush zone, 25% of the crush zone, and/or 100% of the crushzone as a function of the one or more energy absorbing characteristics,wherein energy absorbing characteristics are described in detail below,in reference to FIG. 3 . In an embodiment, secondary crush zone 212 maybe generated as a function of the complete compression of energyabsorbing material 124, wherein secondary crush zone 212 may include anyof the secondary crush zone 212 as described above, in reference to FIG.1 .

Now referring top FIG. 3 , an exemplary embodiment 300 of an energyabsorbing characteristic 304 is illustrated. As used in this disclosurean “energy absorbing characteristic” is one or more qualities associatedwith energy absorption and/or failure safety. In an embodiment andwithout limitation, energy absorbing characteristic 304 may include aconductivity characteristic 308. As used in this disclosure a“conductivity characteristic” is an ability to transmit and/or resistelectric current. For example, and without limitation conductivitycharacteristic 308 may include one or more measurable values associatedwith conductivity such as resistivity, conductivity, temperature, and/orcomposition such as, but not limited to superconductors, metals,semiconductors, insulators, super insulators, and the like thereof. Inan embodiment, and without limitation, conductivity characteristic 30may denote one or more qualities that aid in reducing thermal runaway topromote failure safety. In an embodiment, and without limitation, energyabsorbing characteristic 304 may include a flame resistancecharacteristic 312. As used in this disclosure a “flame resistancecharacteristic” is an ability to withstand oxidation, burning, and/or afire and maintain functionality. For example, and without limitation,flame resistance characteristic 312 may include one or morefire-resistance rating such as a class 125 rating, class 150 rating,class 350 rating, and the like thereof. As a further non-limitingexample, flame resistance characteristic 312 may denote one or moretime/temperature curves to denote a materials functionality over time asa function of the temperature variances during a fire.

In an embodiment, and still referring to FIG. 3 , energy absorbingcharacteristic 304 may include a density characteristic 316. As used inthis disclosure a “density characteristic” is a measurable valueassociated with a mass per unit volume. For example, and withoutlimitation density characteristic may denote that a foam has a 22 poundsper cubic foot denoting a high density. As a further non-limitingexample, density characteristic may include one or more buckling and/orcrushing stress values, plateau stress values, and/or densificationstress values. In an embodiment, and without limitation, energyabsorbing characteristic 304 may include an absorption characteristic320. As used in this disclosure an “absorption characteristic” is anability to absorb and/or mitigate an impact and/or shock. For example,and without limitation, absorption characteristic 320 may include one ormore characteristics associated with reducing one or more shockenergies, vibration energies, frequencies, and the like thereof. In anembodiment, and without limitation, energy absorbing characteristic 304may include a structure characteristic 324. As used in this disclosure a“structure characteristic” is a structural formation of the material.For example, and without limitation, structural characteristic 324 mayinclude one or more structures of a material such as, but not limited tohexagonal structure, triangular structure, rectangular structure, andthe like thereof. In an embodiment and without limitation, structurecharacteristic 324 may denote a honeycomb structure of a material and/ora sandwich structured compositive structure consisting of a plurality oflayers with a plurality of structures.

Referring now to FIG. 4 , an exemplary embodiment of an aircraft 400 isillustrated. In embodiments, electrically powered aircraft 400 may be anelectric vertical takeoff and landing (eVTOL) aircraft. Electricallypowered aircraft 400 may include pack casing 104 located underneath thefuselage of the aircraft. Electrically power aircraft may include one ormore flight control elements 404A-N. As used in this disclosure a flightcontrol element” is a component that can be moved and/or adjusted toaffect altitude, airspeed velocity, groundspeed velocity, and/ordirection during flight. For example, flight control element 404A-N mayinclude a component used to affect the aircrafts' roll and pitch whichmay comprise one or more ailerons, defined herein as hinged surfaceswhich form part of the trailing edge of each wing in a fixed wingaircraft, and which may be moved via mechanical means such as withoutlimitation servomotors, mechanical linkages, or the like, to name a few.As a further example, a flight control element 404A-N may include arudder, which may include, without limitation, a segmented rudder. Therudder may function, without limitation, to control yaw of an aircraft.Also, a flight control element 404A-N may include other flight controlsurfaces such as propulsors, rotating flight controls, or any otherstructural features which can adjust the movement of the aircraft.

Still referring to FIG. 4 , a flight control element 404 may include atleast a propulsor. A propulsor, as used herein, is a component or deviceused to propel a craft by exerting force on a fluid medium, which mayinclude a gaseous medium such as air or a liquid medium such as water.In an embodiment, when a propulsor twists and pulls air behind it, itwill, at the same time, push an aircraft forward with an equal amount offorce. The more air pulled behind an aircraft, the greater the forcewith which the aircraft is pushed forward. Propulsor may include anydevice or component that consumes electrical power on demand to propelan electric aircraft in a direction or other vehicle while on ground orin-flight.

Still referring to FIG. 4 , electric aircraft 400 may be capable ofrotor-based cruising flight, rotor-based takeoff, rotor-based landing,fixed-wing cruising flight, airplane-style takeoff, airplane-stylelanding, and/or any combination thereof. Rotor-based flight, asdescribed herein, is where the aircraft generated lift and propulsion byway of one or more powered rotors coupled with an engine, such as a“quad copter,” multi-rotor helicopter, or other vehicle that maintainsits lift primarily using downward thrusting propulsors. Fixed-wingflight, as described herein, is where the aircraft is capable of flightusing wings and/or foils that generate life caused by the aircraft'sforward airspeed and the shape of the wings and/or foils, such asairplane-style flight.

Continuing to refer to FIG. 4 , an illustration of forces is illustratedin an electric aircraft. During flight, a number of forces may act uponthe electric aircraft. Forces acting on an aircraft 400 during flightmay include thrust, the forward force produced by the rotating elementof the aircraft 400 and acts parallel to the longitudinal axis. Drag maybe defined as a rearward retarding force which is caused by disruptionof airflow by any protruding surface of the aircraft 400 such as,without limitation, the wing, rotor, and fuselage. Drag may opposethrust and acts rearward parallel to the relative wind. Another forceacting on aircraft 400 may include weight, which may include a combinedload of the aircraft 400 itself, crew, baggage and fuel. Weight may pullaircraft 400 downward due to the force of gravity. An additional forceacting on aircraft 400 may include lift, which may act to oppose thedownward force of weight and may be produced by the dynamic effect ofair acting on the airfoil and/or downward thrust from at least apropulsor. Lift generated by the airfoil may depends on speed ofairflow, density of air, total area of an airfoil and/or segmentthereof, and/or an angle of attack between air and the airfoil.

The foregoing has been a detailed description of illustrativeembodiments of the invention. Various modifications and additions can bemade without departing from the spirit and scope of this invention.Features of each of the various embodiments described above may becombined with features of other described embodiments as appropriate inorder to provide a multiplicity of feature combinations in associatednew embodiments. Furthermore, while the foregoing describes a number ofseparate embodiments, what has been described herein is merelyillustrative of the application of the principles of the presentinvention. Additionally, although particular methods herein may beillustrated and/or described as being performed in a specific order, theordering is highly variable within ordinary skill to achieve embodimentsaccording to this disclosure. Accordingly, this description is meant tobe taken only by way of example, and not to otherwise limit the scope ofthis invention.

Exemplary embodiments have been disclosed above and illustrated in theaccompanying drawings. It will be understood by those skilled in the artthat various changes, omissions and additions may be made to that whichis specifically disclosed herein without departing from the spirit andscope of the present invention.

What is claimed is:
 1. An electric aircraft with a battery pack forfailure safety, the electric aircraft comprising: a fuselage having alongitudinal axis; and a battery pack disposed within the fuselage,wherein the battery pack comprises: a pack casing mounted to thefuselage, wherein the pack casing comprises an inner lining; and a crushzone positioned perpendicular to the longitudinal axis, wherein thecrush zone comprises an energy absorbing material configured to compressas a function of a crash force.
 2. The electric aircraft of claim 1,wherein the pack casing comprises an upper wall positioned opposite ofthe crush zone.
 3. The electric aircraft of claim 2, wherein the upperwall of the pack casing includes a recess located along a centrallongitudinal axis.
 4. The electric aircraft of claim 2, furthercomprising a secondary crush zone that is located adjacent to the upperwall, wherein the secondary crush zone is generated as a function of acompression of the energy absorbing material.
 5. The electric aircraftof claim 1, wherein the pack casing includes an external shell.
 6. Theelectric aircraft of claim 1, wherein the pack casing comprises at leasta side wall configured with a high compression strength element.
 7. Theelectric aircraft of claim 6, wherein the high compression strengthelement comprises a honeycomb arrangement.
 8. The electric aircraft ofclaim 6, wherein the at least a side wall is configured to secure aninner lining of the pack casing.
 9. The electric aircraft of claim 1,wherein the pack casing comprises a lower wall.
 10. The electricaircraft of claim 9, wherein: the crush zone is located adjacent to thelower wall of the pack casing; and the crush zone comprises a thicknessparameter.
 11. The electric aircraft of claim 1, wherein the energyabsorbing material is composed of a compressible material.
 12. Theelectric aircraft of claim 1, wherein the energy absorbing materialincludes polyether ether ketone.
 13. The electric aircraft of claim 1,wherein the energy absorbing material includes polymer foam.
 14. Theelectric aircraft of claim 1, wherein the energy absorbing material isconfigured to absorb a predetermined amount of force.
 15. The electricaircraft of claim 1, wherein the energy absorbing material is configuredto absorb a predetermined direction of force.
 16. The electric aircraftof claim 1, wherein: the energy absorbing material includes an energyabsorbing characteristic; and the energy absorbing characteristiccomprises a conductivity characteristic.
 17. The electric aircraft ofclaim 1, wherein: the energy absorbing material includes an energyabsorbing characteristic; and the energy absorbing characteristiccomprises a flame resistance characteristic.
 18. The electric aircraftof claim 1, wherein the crush zone is configured to reduce an impactforce.
 19. The electric aircraft of claim 1, wherein the crush zone isconfigured to prevent a thermal runaway of the battery module.
 20. Theelectric aircraft of claim 1, further comprising at least a flightcontrol element configured to affect flight of the electric aircraft.